Cheats
Enable cheats for 30 seconds:
up up down down left right left

restore life:
L3 + right

restore time dilation:
L3 + up 

Get More Plasm
To get more "Plasm" points from each kill, get in as many consecutive hits as possible. The more consecutive hits you get, the more damage you do and the more plasm you get from each kill... which essentially means more powerups faster!

Kill enemies faster
When fighting an enemy switch to sword mode and walk up to an enemy and press o. when they go up in the air wait till they come low enough for you to hit them the press o again this one more time and this time when the come down do a shining sword (press square) to finish them off fast.